Oil recovery systems exist that incorporate a floating boom type collection apparatus. In the usual floating boom apparatus, each end of a U-shaped boom is drawn forward through the spill area and the floating oil is collected at the rear, closed end of the boom, wherefrom it can be recovered. This type of system generally requires three vessels to operate, one towing each of the front ends and one at the rear end to collect the oil. An example of such an oil recovery system is disclosed by U.S. Pat. No. 4,388,188. A three vessel system is costly to operate, requires time to deploy and requires difficult coordinated navigation while in operation. In addition, a three vessel system is ineffective in rough weather where heavy seas may move the vessels relative to one another, resulting in a failure of the oil boom. The deployment time is especially critical in cases involving spills that can be easily contained only in the earliest stages before substantial spreading has occurred.
Single vessel operated oil recovery systems are known, as in U.S. Pat. No. 3,771,662, in FIG. 1-B. However, known single vessel systems tow the containment boom immediately behind the vessel. As a result, the turbulence and increased water flow behind the propeller of the vessel makes recovery difficult by mixing oil and water in the containment area and by churning some of the oil to depths where containment is not possible.
Another disadvantage of known single vessel recovery systems is the difficulty of keeping the front of the boom open to a sufficient width to enable a large area of water to be skimmed. A vessel whose recovery zone is narrower than the width of the boat, such as disclosed in U.S Pat. No. 4,597,863, is useful only for very small spills in very small areas. Minor improvements have been achieved as by extending oil collection booms from the sides of the vessels as in U.S. Pat. No. 4,673,497, to divert oil to collection ports in the vessel's sides, but such options are not useful for large spill areas. Larger spill areas may be skimmed by dedicated vessels with large containment booms, such as disclosed in U.S. Pat. No. 3,348,690, but such systems are not easily and rapidly adaptable to ordinary ocean-going vessels, such as those that might be in the vicinity and therefore capable of a rapid response.